Leinster have named their team for this weekend's Champions Cup semi-final against Scarlets.

Robbie Henshaw returns for his first game since since Montpellier away in January.

As reported in today's Irish Independent, Luke McGrath has not recovered from his ankle issue in time to play.

James Lowe misses out on the biggest game of the province's season due to the competition rules on non-European players with Scott Fardy and Jamison Gibson-Park are both named to start.

The return of Henshaw to the midfield allows Isa Nacewa to shift out to the wing in Lowe's place, with the Ireland star back ahead of schedule after suffering a serious shoulder injury against Italy in the Six Nations.

Johnny Sexton will captain Leinster tomorrow despite regular skipper Nacewa also included in the starting XV.

After this morning's captain's run at the Aviva Stadium, Leo Cullen confirmed that a decision was taken earlier in the week because Nacewa missed training due to illness.

The 35-year old has recovered enough to take his place on the wing, as the fit-again Henshaw returns in midfield.

“The way the week unfolded, Isa was sick at the start of the week,” Cullen explained.

“I think we have used nine captains this year across the games so far. Johnny and Isa are the two main leaders.

“With Isa missing the start of the week and coming back in on the wing as well, it's important that we are able to have the ability to share to load.

“That's the big thing from our end in terms of, this is a one-off game and we treat it as a one-off game. We feel that this is the best for us this week.”

Cullen also confirmed that Sean O'Brien underwent shoulder surgery today and Leinster are currently awaiting word on how long the flanker faces out with his latest setback.

“He was just in with the surgeon this morning so we'll have a report out in due course. I don't actually know the full details myself yet,” the head coach said.

Luke McGrath is said to be “making good progress” but tomorrow's game came too soon for the scrum-half, with Jamison Gibson-Park getting the nod.

Scarlets have named their 23-man squad to face Leinster on Saturday afternoon, with Leigh Halfpenny lining up on the wing.

The two-time British and Irish Lion will wear the number 14 jersey due to the absence of Paul Asquith, Johnny McNicholl and Tom Prydie through injury.

Rhys Patchell, who usually plays as an out-half, will shift to full-back, a position he has filled at times this season.